Molding die



Patented; July 14, 1936 MOLDING DIE George C. Maison, Brookiield, 111., assignor to Y Western Electric Company, Incorporated, New York, N. Y., a corporation oi New York Application January 11, 1934, Serial No. 706,186

2 Claims. (01. 18-42) This invention relates to a molding die, and more particularly to a die for molding threaded articles.

An object of the invention is to provide an em- 5 cient and practical die for molding articles and simultaneously forming threads on the articles.

In accordance with the object, one embodiment of the invention contemplates the provisionoi a movable mold section carrying a plunger recessed to form a portion of a mold cavity, a fixed mold section recessed to receive the plunger and to.

form another portion of the mold cavity, an element threadedly disposed in the fixed mold section for forming the interior of the article and for forming threads thereon, means for. rotating the element for removing it from the article when finished, and means for removing the article from the mold cavity.

Other objects and advantages will be apparent 20 from the following detailed description, taken in conjunction with the accompanying drawing, wherein Fig. 1 is a top plan View of a molding die illustrating the invention, portions thereof being broken away, and

Fig. 2 is a vertical sectional view taken along the line 2--2 of Fig. 1.

Referring now to the drawing wherein like reference numerals designate similar parts and which illustrates the invention applied to apparatus for molding caps for collapsible tubes, numeral Ill designates a movable portion of a molding press to which is secured a movable mold section II carrying near the ends thereof guide pins 12 for a purpose hereinafter described. As illustrated in Fig. 1 of the drawing a molding die consists of a plurality of units and each unit is capable of molding two articles simultaneously. In view of the fact that the article molding mechanism for molding each article is identical, the description of one mechanism will apply equally well to each of the others.

Fig. 2 illustrates a plunger 13 fixed to the 45 movable mold section H and recessed at 14 to form a portion of the mold cavity. A fixed mold section I 6 consisting of two parts secured to each other has disposed at each end thereof vertically extending apertures ll arranged to receive 50 the guide pins i2 in the upper ends thereof. The fixed mold section It is recessed at 28 to receive the plunger l3 and to form a portion 2i of the mold cavity. A movable element 22 is threadedly connected to a fixed rim 23 disposed in the. 55 fixed mold section it and has a reduced porpurpose of clearness and simplicity.

tion 24 which extends upwardly through an aperture in the upper portion of the section 16 and into the mold cavity where its upper end is provided with threads 25. The lower portion of the element 22 is rotatably and reciprocably disposed 5 in an aperture 26 of the fixed mold section i6 and has elongated teeth 21 formed on its peripheral surface which interengage teeth 28 of a horizontally movable rack 29. The rack 29 is slidably disposed in a horizontally extending aperture in the fixed mold section I6 and is operated by any suitable power means not shown. The fixed mold section It is mounted upon the stationary base 32 of the molding press.

Positioned beneath. the fixed mold section 16 is an ejecting plate 33 mounted upon a reciprocable ejecting mechanism (not shown) of the moldin press. Fixed to the ejecting plate 33 and extending vertically therefrom are guide pins 35 movably disposed in apertures l1, and ejecting plungers 36 extending through apertures in the fixed mold section It and through the centers of the members 22. The-ejecting plunger 36, which is illustrated at the left (Fig. 2), extends upwardly to a position where its upper end terminates flush with the upper end of the element 22 where it remains during the molding operation.

The article may be molded of any suitable material as, for example, phenol plastic material which is originally in powder form. In molding the articles of such material, the mold may be heated and subsequently cooled in any desired manner, and the means for heating and cooling the mold is not shown in the drawing for the In preparing the mold for a molding operation, the rack 29 is moved to the farthest position to the left (Fig. 2) and while the mold is open a suitable quantity of the powdered material is disposed in the mold cavity 2i and the recess 20. The element 22 is in its uppermost position and the ejecting plunger 36 has its upper end flush with the upper end of the element 22. The movable portion ill of the press is then moved downwardly moving the movable mold section I l with it and forcing the plunger l3 into the recess 20 to the position shown in Fig. 2. The mold is then (or previously) heated to a desired temperature to cause the powdered material, which in the present instance is a composite material such as a powdered phenol condensation product, to flow under the pressure of the plunger and to completelyfill theme-cavity. when using a. moldlng material of the type just mentioned the heat to the and pressure are maintained for a sufficient length of time to cure the material. The heating means (not shown) is then rendered ineffective and a cooling means (not shown) is rendered efiectlve for cooling the mold.

After the mold is cooled, the rack 29 is moved. causing a counterclockwise i it div n g and removal bf the element 22 from the molded article. The olement 22 is guided in its downward movement by the walls of the aperture 26 and is moved;clear;.

of the article by its'threaded connee on wlth the ring 23 so that the arti e' '--'iiv ill -not'f b e; d"

aged during the removal"""of"t emjent 2 number of threads per inch, in ,order' to bring about this result. The movable portion is of the press is then moved upwardly carrying'wlth it the movable mold section ll of v the mold-together with the plunger l3 removing theplunger from the article and spacing it a sufidcient glistanoe above the fixed mold section l6 of th mold -1so that the article may be readilyejgetcdand i1emoved from the mold. Theejecting rnemberof the press is then moved;upwa ,rdly;moving with. it the ejecting plate Li a-r d .t h e ejqgtmg plunger 36, the action oi the' la'tter-;forcing,-the :;artiole from the mold cavity. it and movlngitto a position sohthat any suitable receiving ne ans (not show may engage the article and remove it toacontainerf I Only a portioniotic unit of the mold has been des'cribed in detail but as il lustrated in Fig. 1 a plurality of molding units, may be operated simultaneously formolding a plurality of articles Each rack 29 is capable of actuating a plurality of the threaded elements 22, anda plurality of these racks may be simultaneously actuated so that all of the articles made in one assembly may be simultaneously ejected.

Although a specific form of mold has been de scribed as being capable of molding phenol plastic articles, it should be understood that the mold is capable of other modifications and adapie iana w l alil d iin s be d'r'tbe, a ndedib' whatis'ciaihiea'is: 1. In a mold, separable mold sections cooperrating to form a mold cavity and having provi jslongrespectively for connection to the movable and fined portions of a press, an externally jfthreadedjelernent irtending into the cavity for 'fformlng interna threads on the article to be The portion 25 and the collar 21' have the same molded,'said element being connected to one of .said die sections by threads of the same pitch at a point in close proximity to the mold cavity, said element being longitudinally apertured, an ejector: in saidaperture, means for rotating said threaded element-to withdraw it from the article, and means more remote from the die cavity for operating said ejector.

. 2. In a multiple mold, separable mold sections having cooperatingportions forming a. plurality .of mold cavities, and having threaded elements extending into the cavities for forming threads :01: the; articles to be molded, said elements being-connected to one of said die sections by threads of the-same pitch at points in close proximity to thecavities, and means for withdraw ing theelements from the articles comprising an axially elongatedminion closely adjacent to the second-mentioned threads on each element and 3 a common actuating rack whereby upon actuation of the rack the pinions' move' axially without becoming disengaged from the racks.

. GEORGE c. MATSON. 

